Annealing furnace



G. E. SORENSEN. ANNEALING FUR'NACE.

- l I A APPLICATION man oc .1. 1pm'. 1,406,424, Y Patented Feb. 14,1922.

I t 'l n s 2 SHrETs-SHEET 2.

To en Mam may ee-eem Application nle'd October 17, 1919. lSerial No.v 331,385.

Be it 4kn'own'that I, CHARLES SoiniNsiiN,

K- a citizen ofthe United States of America,

, furnace,

residing at Dearborn, in the county" of Wayneand State of Michigan, have invented certain new and useful l "fpi'fovements in.

Aniiealing. Furnaces, of wh therein to the 'accompanying drawings. f

This invention relates- Ato an lannealing and the primary` object .of my in*- f urnish a furnace ofthe above of chambers, oneor vention isto type with 'a plurality more .of'which serve as lcooling chambers for reducing the temperature of stock from j above critical points or stages'to la tempera# ture below' the critical pointsorstages, thus placed in or passin throughtliefurnace.v

Another object o `vmy invention is to pro-. vide la fumiace'wherein` a speedy drop' iny d temperature maybe obtained'fromnn in-- ital heat to afsecond heat, and provision is pieces Vof made for automatically conducting stock or a manner thatl theiheat treatment. may as;

sure uniformity 'and' at'the same time permit of operations beingggeconomically yand expeditiously carried on; f Y 1.5'. Y

The above 'andotlier objects'arejattained by a furnacestructuie of noyelfd'esign in many particularsyqand thesewillv be bestl understood by first considering thedraw- 'ings and then. but when reviewing 'the matter, it is tobe T understood t that the preferred'form of furvnace -hasxbeen illustrated, since it is .in-use,

he detail descriptionthereof,

Y andlthat the 'same principle may be involved in a manychambered furnace of-greater c apacityor size.

`$Reference will now be had to the drawin` ,jiwlierein .glireill is a .longitudinalL sectional view same,

of the'annealing furnace; v 4 'L Fig. 2'is a horizontal sectional view of the showingl two different planes .on which the section is taken, and

Fig. iszfa verticalcross sectional View vof the furnace.

In the drawings, the reference numeral'l` denotes a suitable foundation havingV an up,

A per nclinedgfsurface and'` erected thereon is an oblongffurnace structure comprising a base 3, side walls 4,- front wall 5 and a rear.

"fthe following is a specification, reference being had work .through thefurnacejand in simply ings 13 in the Side walls of the chamber, and 85 the distinction between these two chambers 516 `on said rails.

titions 18 is such as todivideihe furnace soRENsEN,1 .oF'nnARBoBN-, MICHIGAN, assmNoit To HENRY Foizn'asoN; y

A- coRroRA'rioN or MICHIGAN.

annulaire' numerica.

` -fp'e'c'iiatiifremnant- Patented Feb. 14, 1922.

vwalll,*said side wall supporting-an arched ab 'roof 7 .and the entire'structuretied and '.bound so as ,to withstand the heat to which it is4 subjected.` The furnace base' 3 and the found ation=1, ,inay.be r'ahomo eneous mass` .to preclude/any. danger of the. urnace 'being-60- displaced Orlshifting relativeto its foundation andwith--thefurnace "arallel-With the I upper surface ofthe fogiiii sar'ily at .an inclinatio ingend 'of he furnace a T he hearth ef jthe @nieceineiiee .two f 'cliainbers and' 9 separatediby a solid .par-#Q l titionorstiucture 10 andf the chamber 9 1 slightly greater n area than the chamber 8L The chamber. 9 is served by three or lmore burners placedfat openings 111 in- `the-slide `Walls of the chamber 9 and in the front wall s75-` y 5.of the furnace proper. The burnersv may be of a conventional form of o'il orzgas burn lnltype'and within the chamber 9 are flame ba es 12 which also serve-as supports for'the roof ofthe chamber 9 and the bottom of the 80 furnace proper. f l

The chamber is somewhat similar t'o the chamber 9 -With the exception that itis erved b y two burners placed at .openwill be hereinafter referred to.

vThe base 3 ofthe furnace provides a fur' A `nace floor 14 serving as laghearth throughout the length of said furnace. Extending longitudinally of the floor'14 are rails 15 which [have the forward or' upper ends thereof protruding out of the front wall 5of the furnace. so that piecesofwork or. stock 16"'inayl n u be placed thereon'to descend by gravity vand 95 be discharged at therear wall' ofthe furnace.v The pass'a e` of the stock throu h lthe furnace is contro edjb'y a conventiona form of escape'jnent devicel? adapted to be intermittently actuated to feed stock out ofthe furnace after all predetermined heat -treat- Y l 4ment within the furnace. "i

The'roof 7 of `hefurnace is with transverse ail cooled partitions or baffle members'18 extendin Atowards the rails 15 105 aiidjust providing, c earancefor the stock The location of, thepartf a fgrea' tei'felevation. 65 thanthedischarge end thereof so thatpieces .of work orstock maygpassthroughf'th Y.

20 tion to 40 burners,

55 tively heated to proper Ainto threei compartmentsor cham bers 19', 20 and 21. The compartment v19 is at the forward or upper end 'of the furnace above the chamber 9 and heat from 6 said chamber is conducted to the compartment 19 by a. plurality of iues or conduits 22 in the side walls 4 of the furnace,` they' heat being admitted tothe compartmnetv adjacent the roof 7 so as to be deflected dlrectly 10 onthe stock passing through said comnartment.' TheV compartment maybe consi ered the annealing compartment as the temperature therein 1s maintained much higher than the compartments and 21, and with the 15 rails 5 protruding from the front end of the stock therein practically closes the front end of said compartment.

i ends of the furnace and ,directly above the solid partition between the chambers 8 'and 30 9. and this intermediate compartment may be considered a cooling compartment and its temperature will be considerably below Vthat of the annealing compartment 19.

The compartment 21 is above the chamber 8, and heat from said cli/amber is conducted to the compartment v21-`b`yaplurality of fiues or conduits 23 in the sidewalls of the fur- "nace,'and.s'ince'the chamber 8 is of less area than the chamber 9 and served by fewer it is obvious thatthe temperature in the compartment 2l .Will -be' lower than the annealing compartment 19, but higher than .the cooling compartment 20.

. AsJwill'be 'understood from the Aabove dis` 4 5 closure, I have provided an annealing fur.- nace wherein the stock 1s movable therethrough to permit treatment thereby, and in which the stock is subjected to zones :of heat y which vary as to temperature values with an intermediate zone ofless temperature value thanthef'zones adjacent thereto, this result being obtained by the use of a succession of compartments arranged in such manner that while two spaced apartments are each'posiproduce definite temperature values, the intermediate compartment is not heated, and, in the disclosure, is arranged over a portion of the hearth ofthe furnace so arranged as to tend toreduce the tempera-A ture conditions of the compartment'abovejt,

the length of this unheated portion-shofwn as of solid formationbeing such as to practically prevent materiall heat coundctio'n to such intermediate compartment. As, a re- 6 5 sult, such-intermediate compartment forms ie compartment 20 is intermediate theI a desired degree floaded or stock obtained.

a zone'in which the of the compartmentsl at 4the opposite ends of such zone, it being understood, of course, that such' intermediate Zone will necessarily have a temperature value above that of theA atmosphere, since it is unobstructed by doors from adjacent compartments, and the heated stock from compartment 19 is delivered thereinto, vso that this compartment may be consideredl as one for subjecting the stock to heat.

As a result, the temperature drop `desired in succession-to the primary annealingtreat` ment, may be had stock to the variations in atmospheric conditions in immediate succession to the ac tual annealing action, and yet permitting the stock to pass from the furnace in a heated condition, bysubjecting the stock to the ac tion of compartment 21 after leaving the 'compartment of lowest heating value. Hence, it'will be understood that the arrangement sets up conditions-of setting the rstock following the annealing temperature application, and then preparingit for dischargefrorri the furnace.

Since the compartment 20 is at the lower or dischargeend of the furnace, the stock afn ter leaving'vthe cooling compartment 2O is t raised to a `temperature which insures absolute uniformity in the stock before it is discharged from the furnace, consequently there can be not variations in the heat'treatment of the stockdue to climatic conditions at the discharge end of the' furnace. In other 'words, instead of immediately 'discharging the annealed stock to the atmospherel that Without subjecting the may hourly vary in temperature, thestock is uniformly cooledl in the .chamber 20 thus insuring the properdegree of hard ness after 'the Aannealing treatment. The. interposed compartment 214 therefore prevents the atmosphere from interfering Where the stock may beproperly set for of hardness, and "I attach considerable importance to the location of thisfcooling compartment, particularly the fact that it obviates the necessity of a cessation in the operation of thedurnace, as is the usual practice when the furnace Ais to be 1111-' With my furnace the operation o f annealing can be continument depends on the nature of the hearth and the time the stock'is retained Within the -with the cooling in the compartment'20,

lously carried on and the degree of heat treat.-

furnace, both of which may be varied for different kinds of stock. j

' As shown in the drawings, the rails 15 permit of rollable stock passing through the furnace by gravity, cannot roll it is and with such stock that possible to place the furnaceV at a desired inclination so that the stock may slide therethrough.

A Then again,..it is possible to substitute a conveyor which may. be j continuously or intermittently actuated to conduct various kinds of stock through the pa-rtments.

-ed compartments,

hearth to the opposite end annealing furnace.

What I claim is:-

-1. An annealing furnace comprisingI -a hearth, compartments above said hearth, and heating means for end portions of said hearth so that themiddle portion of said hearth and the compartment 'above it are relatively cool. Q. A furnace as characterized in claim 1 wherein the compartments are devoid of doors and disposed in a plane so that stock may pass therethrough by gravity.

3. An annealing 'furnace comprising heata cooling compartment between said heated compartments, and stock supporting means extending through lall of said compartments.

4. An annealing furnace comprising aninclined structure having an annealing compartmentat its upper end, a discharge compartment it its lower end, and a cooling compartment intermediate its ends, and heating means for said annealing and discharge ,com-

5. Aln annealing furnace having a hearth on which stock may roll from end. of the thereof, and holhow partitions depending from the roof of said furnace and providing just sufficient clearance for stock to pass thereunder, so that said partition will afford compartments in said furnace which may be maintained at different temperatures.

6. An annealing furnace comprising an inclined structure adapted to receive stock at its upper yend and discharge -stock at its lower end,=mea`ns extending-.in proximity to the bottom of said structure partitioning said structureinto compartments, separate heatmg means forsome of said compartments, and means adapted to regulate thel passage of stock through g the compartments of said structure..

` 7 A furnaceof the type described comprising chambers in a common plane with a passage with the heating means for said chambers, compartments above Isaid chambers adapted to be heated therefrom, and a cooling' compartment above said partition.

I 8. A furnace as characterized in claim wherein additional means is adapted to.

cause stock to pass from one compartment to another. j y "QX 9. In an annealmg furnace having a travel pathy for the passage of stock therethrough, imeans operative on the stock during its passage for subjecting it to Zones of heat varying as to mediate Zone of less temperature value than the temperature'values of the zones adjacent thereto.

10. In 'an annealing furnace wherein the stock ispassed throughA a succession of compartments, means operative to subject the stock to zones of heat treatment during, its v temperature values of the several Zones such that the Astock is'subjected to a zone of setting temperature in succes'- sion to' the action of the zone' of annealing temperature and then subjected t'o'a zone of vtemperature preliminaryto discharge from the furnace, with the latter zone having its 4temperature value hifrher `than that of the setting zone and less than that of the annealing zone. Y*

11. A furnace as in' claim 101 characterized in thatthe zones are equal in number to the Anumber of compartments.

12. A furnace as in claim 9characterized by heat is applied, with the adjacent Compartments having'positive heating means and the intermediate compartment free from such means.

Intestimony whereof I afliX my signature inthe presence of two witnesses.

CHARLES SORENSEN.

Witnesses:

HARRY V. FISHER, J. RUSSELL GNAU.

a succession of compartments wherein the temperature values, with an inter- 

